1,2

Also numbers n such that (19*10^n+71)/9 is prime.

Makoto Kamada, Factorizations of 211...119.

Index entries for primes involving repunits.

Do[ If[ PrimeQ[(19*10^n + 71)/9], Print[n]], {n, 0, 10000}]

Sequence in context: A092623 A098591 A142386 this_sequence A118818 A142437 A138665

Adjacent sequences: A102947 A102948 A102949 this_sequence A102951 A102952 A102953

more,nonn

Robert G. Wilson v (rgwv(AT)rgwv.com), Dec 17 2004